"We've surpassed the computational potential of this system relative to classical computers by something like 10 to the [power of] 80, which is 80 orders of magnitude, a really enormous number," the University of Sydney's Dr Michael Biercuk told AM.

I don't think that these things are designed for those types of tasks, so probably not, rather it's just about calculating physics using the real thing rather than a poor horribly-complex mechanical simulation of reality.

The quantum computer will move to a stage where it is so far out in front and performing such complex tasks it will be difficult to check if it is working accurately. "They're not easily checked by a classical computer which opens a whole variety of problems," Dr Biercuk said.

In quantum computing, a qubit or quantum bit is a unit of quantum information—the quantum analogue of the classical bit—with additional dimensions associated to the quantum properties of a physical atom. The physical construction of a quantum computer is itself an arrangement of entangled atoms, and the qubit represents[clarification needed] both the state memory and the state of entanglement in a system. A quantum computation is performed by initializing a system of qubits with a quantum algorithm —"initialization" here referring to some advanced physical process that puts the system into an entangled state.

The qubit is described by a quantum state in a two-state quantum-mechanical system, which is formally equivalent to a two-dimensional vector space over the complex numbers. One example of a two-state quantum system is the polarization of a single photon: here the two states are vertical polarization and horizontal polarization. In a classical system, a bit would have to be in one state or the other, but quantum mechanics allows the qubit to be in a superposition of both states at the same time, a property which is fundamental to quantum computing.

Don't understand how they can use a crytsal to compute anything. Someone explain?

I could tell you but you wouldn't be able to verify my answer without a quantum computer.

My understanding is that it's a crystal which can have multiple configuration states. Inserting some energy (maybe via laser) will cause the crystal to have a different state, and then possibly be stable in that state. So instead of a light bulb which has two states with energy (on and off) you have a crystal with many states, which means you perform calculations in a fundamentally different way.

Yeah that's the article. Gave up reading the summary though, I've never followed the explanations of quantum computing between:

"QBits are strange, with states of either 0, 1, or somewhere between" (3 states? Infinite states? Or something else?)
to
"Quantum Computers are thus incredibly powerful"

The closest that I think I've come to understanding the problem was when somewhere or other described it as an interconnected system of all-possibilities which collapses into the probable answer due to human-brain-incompatible non-mechanical properties of reality.

It's in Nature, but I just meant that he touches on "what do we mean by crystal" in the video (i.e. it's an artificial construct).

Nope that wasn't my question (probably yours!). I was asking how the crystal is used as a cpu, from the video you posted and what pinky said it sounds like they use the crystal for simulating quantum computing. Input is the laser (energy), somehow the configuration of the individual atoms is the out put or their spin or their charge or their magnetic field or a bunch of stuff.

Nerfy this part from wiki might explain:

A classical computer has a memory made up of bits, where each bit represents either a one or a zero. A quantum computer maintains a sequence of qubits. A single qubit can represent a one, a zero, or, crucially, any quantum superposition of these two qubit states; moreover, a pair of qubits can be in any quantum superposition of 4 states, and three qubits in any superposition of 8. In general, a quantum computer with qubits can be in an arbitrary superposition of up to different states simultaneously (this compares to a normal computer that can only be in one of these states at any one time). A quantum computer operates by manipulating those qubits with a fixed sequence of quantum logic gates. The sequence of gates to be applied is called a quantum algorithm.

Yeah that does help a little. I get the impression that it somehow goes through all the possible calculations, or would if the universe allowed it, but somehow spits out, or collapses into (whatever that means exactly) a single answer (in a task such as cracking a code, where it can only result in one valid answer, perhaps).

No, not quite - they're very good at some problems, and pretty rubbish at others. For instance: one of the famous ones that they're quite good at, prime factorisation of large numbers, works by running the superposition through a series of 'gates' that in effect perform a Fourier transform of the wavefunction, where the resulting frequencies are the factors you seek (within a certain degree of probability). It's not like it uses the superposition to brute force the answer in a similar style to conventional methods.

You can't just run any old algorithm through a quantum computer.

It's possibly also worth mentioning that the article says that this breakthrough provides a /special case/ of quantum computing -- a quantum simulation -- and not a full-blown quantum computer. The D-Wave machine is also a special case that can only handle specific types of problems, and has been around for a while. That said, this sounds a lot closer, and is definitely a cool breakthrough.

A quantum computer would be able to compute the answer to the above questions for all possibilities in a single operation. Because in quantum mechanics everything is rated in a percentage chance of happening.

A computer would have to brute force every permutation of combinations of those three numbers (each one a new operation - consuming power) within a reasonable range (aka 0 through to 10).

The strength of quantum computing seams to come from the fact that it does literally every single permutation in a single operation.

Please correct me if im wrong... i'm still trying to get my head around it myself. It never seams to get cleaer despite how many youtube vids I watch.

O sweet, I figured that quantum computers would really only be suited to solve problems that involve quantum probabilities (or whatever you call it). I think there are two distinct quantum computer types in development.

The first type use quantum magic to solve quantum problems, things like simulating magnetic fields and whatnot.

The other type is a computer that uses particles of light to do conventional calculations and is basically just a computer that runs close to the speed of light, possibly not even really a quantum computer.
I guess there will be hybrids too.